如何将按钮添加到collectionview单元格

Question

目前我有collectionview个单元格，可以从library加载图片。我希望在此之前添加一个带按钮的单元格来打开camera。我该怎么做??

import UIKit
import Photos
import MobileCoreServices
private let reuseIdentifier = "PhotoCell"
class AddPhotoViewController: UIViewController , UIImagePickerControllerDelegate ,UINavigationControllerDelegate ,UICollectionViewDataSource ,UICollectionViewDelegate{

    @IBOutlet weak var photoAlbum: UICollectionView!

    var TakenImage : UIImageView!
    var selectedImage : UIImage!
    var pickedImage : UIImage!
    var assetCollection: PHAssetCollection!
    var photosAsset: PHFetchResult!
    var assetThumbnailSize: CGSize!
    let imagePicker: UIImagePickerController! = UIImagePickerController()
    var cameraon : Bool = false
    var index : [NSIndexPath]!

    var note : String!
    var noteAlreadyEntered = false
    override func viewDidLoad()
    {
        super.viewDidLoad()

        let collection:PHFetchResult = PHAssetCollection.fetchAssetCollectionsWithType(.SmartAlbum, subtype: .SmartAlbumUserLibrary, options: nil)

        var i = 0
        repeat
        {
            if let first_Obj:AnyObject = collection.objectAtIndex(i)
            {
                self.assetCollection = first_Obj as! PHAssetCollection
            }
            i++
        }while( i < collection.count)



        // Do any additional setup after loading the view.
    }

    @IBAction func takePhoto(sender: AnyObject) {

        let picker = UIImagePickerController()
        picker.delegate = self
        picker.sourceType = .Camera
        presentViewController(picker, animated: true,completion : nil)
        save(TakenImage.image!)


    }
    func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject])
    {

        TakenImage.image = info[UIImagePickerControllerOriginalImage] as? UIImage ; dismissViewControllerAnimated(true, completion: nil )

    }
    @IBAction func save(sender: AnyObject)
    {
        UIImageWriteToSavedPhotosAlbum(TakenImage.image!, self, "image:didFinishSavingWithError:contextInfo:", nil)
    }
    func image(image: UIImage, didFinishSavingWithError error: NSError?, contextInfo:UnsafePointer<Void>)
    {
        if error == nil {
            let ac = UIAlertController(title: "Saved!", message: "Your altered image has been saved to your photos.", preferredStyle: .Alert)
            ac.addAction(UIAlertAction(title: "OK", style: .Default, handler: nil))
            presentViewController(ac, animated: true, completion: nil)
        } else
        {
            let ac = UIAlertController(title: "Save error", message: error?.localizedDescription, preferredStyle: .Alert)
            ac.addAction(UIAlertAction(title: "OK", style: .Default, handler: nil))
            presentViewController(ac, animated: true, completion: nil)
        }
    }


        override func viewWillAppear(animated: Bool)
    {
        if let layout = self.photoAlbum!.collectionViewLayout as? UICollectionViewFlowLayout{
            let cellSize = layout.itemSize

            self.assetThumbnailSize = CGSizeMake(cellSize.width, cellSize.height)
        }

        //fetch the photos from collection
        self.photosAsset = PHAsset.fetchAssetsInAssetCollection(self.assetCollection, options: nil)

        self.photoAlbum!.reloadData()


    }

    // MARK: UICollectionViewDelegate

    /*
    // Uncomment this method to specify if the specified item should be selected
    override func collectionView(collectionView: UICollectionView, shouldSelectItemAtIndexPath indexPath: NSIndexPath) -> Bool {
    return true
    }
    */


    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?)
    {
        if (segue.identifier == "savePhoto")
        {
            if let controller : NoteDetailViewController = segue.destinationViewController as? NoteDetailViewController
            {
                controller.takinPhoto = true
             //   controller.imageView2.image = TakenImage.image
                if(noteAlreadyEntered == true)
                {
                    controller.content = note
                    controller.imageView.image = TakenImage.image
                }
                else
                {
                    controller.imageView2.image = TakenImage.image
                }

            }
        }
           if (segue.identifier == "saveSelected")
        {


            let cell = sender as! PhotoAlbumCollectionViewCell
            let indexPath = photoAlbum.indexPathForCell(cell)
            let destVC = segue.destinationViewController as! NoteDetailViewController
            destVC.asset = self.photosAsset[indexPath!.item] as! PHAsset

            destVC.flag = true
            if(noteAlreadyEntered == true)
            {
                destVC.content = note
            }

        }



    }

    func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath)
    {
    }



    func numberOfSectionsInCollectionView(collectionView: UICollectionView) -> Int
    {
        // #warning Incomplete implementation, return the number of sections
        return 1
    }

    func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int
    {
        // #warning Incomplete implementation, return the number of items
        var count: Int = 0

        if(self.photosAsset != nil){
            count = self.photosAsset.count
        }
        print("\(self.photosAsset.count)")
        return count + 1
    }
    func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell
    {
        let cell: PhotoAlbumCollectionViewCell = photoAlbum.dequeueReusableCellWithReuseIdentifier("PhotoCell", forIndexPath: indexPath) as! PhotoAlbumCollectionViewCell

        //Modify the cell
        let asset: PHAsset = self.photosAsset[indexPath.item] as! PHAsset

        PHImageManager.defaultManager().requestImageForAsset(asset, targetSize: self.assetThumbnailSize, contentMode: .AspectFill, options: nil, resultHandler: {(result, info)in
            if let image = result {
                cell.setThumbnailImage(image)
            }
        })

        return cell
    }



    func collectionView(collectinView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAtIndex section: Int) -> CGFloat {
        return 4
    }

    func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAtIndex section: Int) -> CGFloat {
        return 1
    }

    func collectionView(collectionView: UICollectionView, shouldShowMenuForItemAtIndexPath indexPath: NSIndexPath) -> Bool {
        return false
    }

    func collectionView(collectionView: UICollectionView, canPerformAction action: Selector, forItemAtIndexPath indexPath: NSIndexPath, withSender sender: AnyObject?) -> Bool {
        return false
    }

    func collectionView(collectionView: UICollectionView, performAction action: Selector, forItemAtIndexPath indexPath: NSIndexPath, withSender sender: AnyObject?) {

        self.dismissViewControllerAnimated(false, completion: nil)

    }

}

Answer 1

您已经在numberOfItemInSection方法中传递了一个计数。所以只需像这样更改cellForItemAtIndexPath

func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
    let cell: PhotoAlbumCollectionViewCell = photoAlbum.dequeueReusableCellWithReuseIdentifier("PhotoCell", forIndexPath: indexPath) as! PhotoAlbumCollectionViewCell
    if (indexPath.item == 0) {
         let btn = UIButton(frame: cell.contentView.bounds) //Set your frame that you want
         btn.setBackgroundImage(UIImage(named: "add"), forState: .Normal)
         btn.addTarget(self, action: #Selector(addNewImage(_:)), forControlEvents: .TouchUpInside)
         cell.contentView.addSubview(btn)
    }
    else {
        //Modify the cell
        let asset: PHAsset = self.photosAsset[indexPath.item-1] as! PHAsset
        PHImageManager.defaultManager().requestImageForAsset(asset, targetSize: self.assetThumbnailSize, contentMode: .AspectFill, options: nil, resultHandler: {(result, info)in
             if let image = result {
                 cell.setThumbnailImage(image)
             }
         })
     }
     return cell
}

现在只需在addNewImage中添加此ViewController方法，就像这样

func addNewImage(sender: UIButton) {
     //Add the code of ImagePicker
}

要解决segue问题，您需要覆盖shouldPerformSegueWithIdentifier

中的ViewController方法

override func shouldPerformSegueWithIdentifier(identifier: String, sender: AnyObject?) -> Bool {
    if (identifier == "saveSelected")
    {
        let cell = sender as! PhotoAlbumCollectionViewCell
        let indexPath = tableView.indexPathForCell(cell)
        if (indexPath.row == 0) {
            self.addNewImage(UIButton()) // To Open Camera
            return false //To stop perform Segue.
        }
    }
    return true
}

Answer 2

我假设您正在为collectionview单元格使用自定义类，并且已经将相机图像添加到阵列的第一个索引，因为您要添加选项以在图像之前打开相机。这是执行此操作的简单方法。

func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {

let cell = collectionView.dequeueReusableCellWithReuseIdentifier("Identifier", forIndexPath: indexPath) as! YourCustomcell

cell.imageView.image = UIImage(named: arryImage[indexPath.item] as String)

return cell
}
func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath){
   if indexPath.item == 0 {
       //Code to open camera
   }else{

   }        
}

这是实现您想要的最简单方法。如果您不想将相机图像添加到图像数组中，那么只需在numberOfItemsInSection方法中将数组计数增加1，然后在cellForItemAtIndexPath方法中进行以下更改

if indexPath.item == 0 {
           cell.imageView.image = UIImage(named: "CameraImage")
}else{
           cell.imageView.image = UIImage(named: arryImage[(indexPath.item)-1] as String)
}

didSelectItemAtIndexPath方法将保持不变。如果你想在最后使用opencamera函数，那么就进行相应的更改。

希望这会对你有所帮助:)。